An Ultra-Broadband, Integrated Mid-Infrared Photon-Pair Source

Broadband photon-pairs from a parametric down-conversion (PDC) source are essential for quantum optics experiments in the context of spectroscopy, quantum optical coherence tomography and entangled two-photon absorption [1]–[2]. Entangled two-photon absorption benefits from the ultra-short correlation time of a highly time-frequency entangled photon-pair which increases the absorption cross-section while in spectroscopy, broad spectral coverage in the mid-infrared allows one to enter the regime of life science applications.